Analysis of clinical specimens is important in science and medicine. Multiplexed assays to determine qualitative and/or quantitative characteristics of a specimen are known in the art. For example, U.S. Pat. No. 5,981,180 (the “'180 patent”), which is hereby incorporated by reference, discloses methods, instrumentation, and products for detecting multiple analytes in a fluid sample by flow cytometric analysis. The products include bead subsets, each bead subset having a different reactant bound to the bead. The individual subsets are prepared so that beads within a subset are relatively homogenous but differ in at least one distinguishing characteristic from beads in any other subset. Therefore, the subset to which a bead belongs can readily be determined after beads from different subsets are pooled. The methods include pooling the variously labeled subsets prior to assay and mixing the pooled bead set with a fluid sample to test for analytes reactive with the various reactants bound to the beads.
Autoimmunity is a disease condition whereby the body's immune system produces autoantibodies against the body's own normal components, i.e. self-antigens, rather than antibodies against foreign substances, i.e. antigens, to the body. The onset of autoimmune disorder is difficult to diagnose because autoantibodies may be produced from about one month prior to as much as thirty years prior to development of such a disorder. As a result, conducting clinical trials for pharmaceuticals directed to preventing autoimmune disorder is problematic; it is economically and logistically prohibitive to run trials for an unknown length of time and up to thirty years in duration.
There is therefore a need for a method which can better define clinical presentation of autoimmune disorders. Preferably, such a method could enable researchers to identify those patients that would develop disorders in the short term and thus be suitable candidates for clinical trials.